PROBLEM TO BE SOLVED: To provide a low molecular weight peptide having strong antibacterial or antifungal activity independent of salt concentration and having extremely low toxicity to eukaryotic cells, and an antibacterial or antifungal drug using the same. SOLUTION: The following peptides (a), (b) or (c), derivatives thereof or salts thereof. (a) A peptide containing a specific amino acid sequence. (b) A peptide containing an amino acid sequence in which one or several amino acids are deleted, substituted, or added in a specific amino acid sequence, and which has antibacterial or antifungal activity. (c) A peptide containing an amino acid sequence having 80% or more identity with a specific amino acid sequence and having antibacterial or antifungal activity. [Selection diagram] None【課題】塩濃度に左右されない強い抗菌又は抗真菌活性を有し、かつ、真核細胞に対して極めて毒性が低い低分子量のペプチド、及び、それを用いた抗菌又は抗真菌薬の提供。【解決手段】以下の(a)、(b)又は(c)のペプチド、その誘導体又はこれらの塩。(a)特定のアミノ酸配列を含むペプチド。(b)特定のアミノ酸配列において１若しくは数個のアミノ酸が欠失、置換、若しくは、付加されたアミノ酸配列を含み、かつ、抗菌又は抗真菌活性を有するペプチド。(c)特定のアミノ酸配列と80％以上の同一性を有するアミノ酸配列を含み、かつ、抗菌又は抗真菌活性を有するペプチド。【選択図】なし
